/*******************************************************************************
 * Copyright (c) 2011 EclipseDevX.org and others.
 * 
 * All rights reserved. This program and the accompanying materials are made
 * available under the terms of the Eclipse Public License v1.0 which
 * accompanies this distribution, and is available at:
 * 
 *     http://www.eclipse.org/legal/epl-v10.html
 *******************************************************************************/

package org.eclipsedevx.testing;

import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.plugin.AbstractUIPlugin;
import org.osgi.framework.BundleContext;

/**
 * The activator class controls the plug-in life cycle
 */
public class DevXTestingPlugin extends AbstractUIPlugin {

	// The plug-in ID
	public static final String PLUGIN_ID = "org.eclipsedevx.testing";

	// The shared instance
	private static DevXTestingPlugin plugin;
	
	/**
	 * The constructor
	 */
	public DevXTestingPlugin() {
		
	}

	public void start(BundleContext context) throws Exception {
		super.start(context);
		
		plugin = this;
	}

	public void stop(BundleContext context) throws Exception {
		plugin = null;
		
		super.stop(context);
	}

	/**
	 * Returns the shared instance
	 *
	 * @return the shared instance
	 */
	public static DevXTestingPlugin getPlugin() {
		return plugin;
	}

	/**
	 * Get an image given a path relative to this plugin.
	 * 
	 * @param path
	 * @return an image
	 */
	public static Image getImage(String path) {
		if (getPlugin().getImageRegistry().get(path) != null) {
			return getPlugin().getImageRegistry().get(path);
		}

		ImageDescriptor descriptor = findImageDescriptor(path);

		if (descriptor != null) {
			getPlugin().getImageRegistry().put(path, descriptor);

			return getPlugin().getImageRegistry().get(path);
		}

		return null;
	}

	/**
	 * Respects images residing in any plug-in. If path is relative, then this
	 * bundle is looked up for the image, otherwise, for absolute path, first
	 * segment is taken as id of plug-in with image
	 * 
	 * @param path
	 *            the path to image, either absolute (with plug-in id as first
	 *            segment), or relative for bundled images
	 * @return the image descriptor
	 */
	public static ImageDescriptor findImageDescriptor(String path) {
		final IPath p = new Path(path);

		if (p.isAbsolute() && p.segmentCount() > 1) {
			return AbstractUIPlugin.imageDescriptorFromPlugin(p.segment(0), p
					.removeFirstSegments(1).makeAbsolute().toString());
		} else {
			return getBundledImageDescriptor(p.makeAbsolute().toString());
		}
	}

	/**
	 * Returns an image descriptor for the image file at the given plug-in
	 * relative path.
	 * 
	 * @param path
	 *            the path
	 * @return the image descriptor
	 */
	public static ImageDescriptor getBundledImageDescriptor(String path) {
		return AbstractUIPlugin.imageDescriptorFromPlugin(PLUGIN_ID, path);
	}
	
}
